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1.
Sergio Cardoso Laura Valverde Miguel A. Alfonso-Sánchez Leire Palencia-Madrid Xabier Elcoroaristizabal Jaime Algorta Susana Catarino David Arteta Rene J. Herrera María Teresa Zarrabeitia José A. Pe?a Marian M. de Pancorbo 《PloS one》2013,8(7)
The European genetic landscape has been shaped by several human migrations occurred since Paleolithic times. The accumulation of archaeological records and the concordance of different lines of genetic evidence during the last two decades have triggered an interesting debate concerning the role of ancient settlers from the Franco-Cantabrian region in the postglacial resettlement of Europe. Among the Franco-Cantabrian populations, Basques are regarded as one of the oldest and more intriguing human groups of Europe. Recent data on complete mitochondrial DNA genomes focused on macrohaplogroup R0 revealed that Basques harbor some autochthonous lineages, suggesting a genetic continuity since pre-Neolithic times. However, excluding haplogroup H, the most representative lineage of macrohaplogroup R0, the majority of maternal lineages of this area remains virtually unexplored, so that further refinement of the mtDNA phylogeny based on analyses at the highest level of resolution is crucial for a better understanding of the European prehistory. We thus explored the maternal ancestry of 548 autochthonous individuals from various Franco-Cantabrian populations and sequenced 76 mitogenomes of the most representative lineages. Interestingly, we identified three mtDNA haplogroups, U5b1f, J1c5c1 and V22, that proved to be representative of Franco-Cantabria, notably of the Basque population. The seclusion and diversity of these female genetic lineages support a local origin in the Franco-Cantabrian area during the Mesolithic of southwestern Europe, ∼10,000 years before present (YBP), with signals of expansions at ∼3,500 YBP. These findings provide robust evidence of a partial genetic continuity between contemporary autochthonous populations from the Franco-Cantabrian region, specifically the Basques, and Paleolithic/Mesolithic hunter-gatherer groups. Furthermore, our results raise the current proportion (≈15%) of the Franco-Cantabrian maternal gene pool with a putative pre-Neolithic origin to ≈35%, further supporting the notion of a predominant Paleolithic genetic substrate in extant European populations. 相似文献
2.
Valentina Isetta Josep M. Montserrat Raquel Santano Alison J. Wimms Dinesh Ramanan Holger Woehrle Daniel Navajas Ramon Farré 《PloS one》2016,11(3)
Bench testing is a useful method to characterize the response of different automatic positive airway pressure (APAP) devices under well-controlled conditions. However, previous models did not consider the diversity of obstructive sleep apnea (OSA) patients’ characteristics and phenotypes. The objective of this proof-of-concept study was to design a new bench test for realistically simulating an OSA patient’s night, and to implement a one-night example of a typical female phenotype for comparing responses to several currently-available APAP devices. We developed a novel approach aimed at replicating a typical night of sleep which includes different disturbed breathing events, disease severities, sleep/wake phases, body postures and respiratory artefacts. The simulated female OSA patient example that we implemented included periods of wake, light sleep and deep sleep with positional changes and was connected to ten different APAP devices. Flow and pressure readings were recorded; each device was tested twice. The new approach for simulating female OSA patients effectively combined a wide variety of disturbed breathing patterns to mimic the response of a predefined patient type. There were marked differences in response between devices; only three were able to overcome flow limitation to normalize breathing, and only five devices were associated with a residual apnea-hypopnea index of <5/h. In conclusion, bench tests can be designed to simulate specific patient characteristics, and typical stages of sleep, body position, and wake. Each APAP device behaved differently when exposed to this controlled model of a female OSA patient, and should lead to further understanding of OSA treatment. 相似文献
3.
Late Quaternary climate change,relict populations and present‐day refugia in the northern Atacama Desert: a case study from Quebrada La Higuera (18° S) 下载免费PDF全文
4.
Christian Alvarez Glaucia Gon?alves Barbosa Raquel de Vasconcellos Carvalhaes de Oliveira Bernardina Penarrieta Morales Bodo Wanke Márcia dos Santos Lazéra 《Memórias do Instituto Oswaldo Cruz》2013,108(1):126-129
In this study, we evaluated several techniques for the detection of the yeast form of Cryptococcus in decaying wood and measured the viability of these fungi in environmental samples stored in the laboratory. Samples were collected from a tree known to be positive for Cryptococcus and were each inoculated on 10 Niger seed agar (NSA) plates. The conventional technique (CT) yielded a greater number of positive samples and indicated a higher fungal density [in colony forming units per gram of wood (CFU.g-1) ] compared to the humid swab technique (ST). However, the difference in positive and false negative results between the CT-ST was not significant. The threshold of detection for the CT was 0.05.103 CFU.g-1, while the threshold for the ST was greater than 0.1.103 CFU-1. No colonies were recovered using the dry swab technique. We also determined the viability of Cryptococcus in wood samples stored for 45 days at 25ºC using the CT and ST and found that samples not only continued to yield a positive response, but also exhibited an increase in CFU.g-1, suggesting that Cryptococcus is able to grow in stored environmental samples. The ST.1, in which samples collected with swabs were immediately plated on NSA medium, was more efficient and less laborious than either the CT or ST and required approximately 10 min to perform; however, additional studies are needed to validate this technique. 相似文献
5.
6.
Helen L. Jessop Raquel Demarco de Hormaeche Kathryn E. Senior Paul Tonks 《FEMS microbiology letters》1988,55(2):207-212
Abstract Depending on the culture conditions, Pyrodictium occultum cells revealed two different types of fibers with significant differences in their width in the electron microscope. During growth on elemental sulfur preferentially fibres with a diameter of about 23 nm (type I) were produced. When elemental sulfur was substituted by thiosulfate fibers with a diameter of around 15 nm (type II), were the main appendages. Both types form hollow cylinders consisting of helically arranged sub-units with a wall thickness of 2–3 nm. A triple- layered unit membrane could not be found. 相似文献
7.
We measured the production of untargeted mutations in the cI and cII genes of untreated λ phage undergoing a lytic cycle in UV-irradiated bacterial hosts. As previously shown, treatment with 4 μg/ml of rifampicin during post-irradiation incubation inhibited amplification of the RecA protein in these cells. In addition, we observed a decreased mutation rate compared to the untreated, irradiated bacteria. Treatment with 4 μg/ml or 8 μg/ml rifampicin did not prevent the UV induction of the umuDC operon, as judged by assay of β-galactosidase activity in a umuC-lacZ fusion strain. In contrast, the UV-induction of β-galactosidase in the sulA-lacZ fusion strain was decreased by 4 μg/ml rifampicin. The inhibition of untargeted mutagenesis by this drug treatment was also observed in a strain constitutive for SOS functions (lexA (Def)) as well as ina RecA-overproducing plasmid strain, that blocks induction of heat-shock proteins, factor(s) in wild-type recA+ cells. An htpR165-carrying strain, that blocks induction of heat-shock proteins, exhibited normal UV-promoted mutagenesis. A correlation was observed between the cellular concentration of RecA protein, increased spontaneously by a temperature shift in a lexA(Ts) strain, and the extent of UV-promoted untargeted mutagenesis. These results suggest a mechanistic role of RecA protein in this process. 相似文献
8.
Raquel Fernández-Durango José A. de Juan Horatio Zimman Francisco J. Moya Mario Garcia de la Coba Arturo Fernández-Cruz 《Journal of neurochemistry》1994,62(4):1482-1488
Abstract: Specific endothelin (ET) binding sites were characterized in membranes prepared from human cerebral cortices using binding assay and cross-linking analysis. The presence of immunoreactive (IR) ET-1 was studied by radioimmunoassay. Saturation binding experiments revealed that the K D and B max for 125 I-ET-1 and 125 l-ET-3 to membranes from gray matter were 25 ± 6 pM and 115 ± 15 fmol/mg of protein and 24 ± 5 p M and 108 ± 13 fmol/mg of protein, respectively. Similar results were obtained for white matter. In the presence of 10 n M sarafotoxin-6c, which is selective for ETB receptors, 125 I-ET-1 and 125 l-ET-3 binding was totally abolished. However, in the presence of 1 μ M BQ123, which is selective for ETA receptors, both bindings were not affected. These results suggest that the human cerebral cortex contains only ETB receptors. Cross-linking of 125 I-ET-1 and 125 l-ET-3 to membranes with disuccinimidyl suberate resulted in the labeling of two bands of 48 and 31 kDa. Concentrations of IR-ET-1 in the gray and white matter were 7.0 ± 3.2 and 2.5 ± 1.7 fmol/g wet weight, respectively. The demonstration of high-affinity ETB receptors and the presence of IRET-1 suggest that the peptide may act as a neurotransmitter or neuromodulator in the human cerebral cortex. 相似文献
9.
Frida E. Kleiman Raquel Dodelson de Kremer Ana Oller de Ramirez Roy A. Gravel Carlos E. Argaraña 《Human genetics》1994,94(3):279-282
The level of -hexosaminidase activity in plasma and leukocytes and the frequency of three known HEXB mutations were studied in an Argentinean deme with high incidence of infantile Sandhoff disease. Two mutations were previously identified in one of two Sandhoff patients from the region, a splice mutation, IVS-2+1 GA, and a 4-bp deletion, CTTT782–785. These mutations, and a 16kb deletion from the 5' end of the HEXB gene common in non-Argentineans, were screened in 9 Sandhoff patients (all unrelated), 24 obligate heterozygotes, 33 additional individuals belonging to families with affected members, and 64 randomly ascertained individuals from the high risk region. Of 31 independent alleles examined, including those of the two patients previously reported, 30 had the IVS-2 splice mutation and only the originally reported patient had the CTTT deletion. The 16-kb deletion was not observed. Further, among the 57 unaffected members of families with a previous history of Sandhoff disease, and absolute correlation was found between carrier diagnosis by enzyme assay of leukocytes and the DNA-based tests for mutation. One of the 64 controls was classified as a carrier by enzyme assay but did not have one of the three mutations screened. We conclude that a single mutation predominates in this Argentinean population and that the DNA-based test can be an effective supplement or alternative to enzyme-based testing. 相似文献
10.